Means for applying a sensitizing coating to paper



June 29 1926. A 1,590,417

H. J. BRUNK MEANS FOR APPLYING A SENSITIZING COATING TO PAPBR I Filed August 1, 1925 2 Shun-Shut 1 ii "mil Hi k {I l Ewnzof.

June 29 1926. v 1,590,417

H. J. BRUNK MEANS, FOR Arnnue A SENSITIZING comma 10 1mm 2 shun-Shut 2 Filed August 1 1925 Patented June 29, 1926.

UNITED STATES PATENT OFFICE.

HAROLD J. DRUNK, OI CHICAGO, ILLINOIS, ASSIGNOR TO 0. I. PEA.SE COMPANY, A

I CORPORATION 01 ILLINOIS.

MEANS FOR APPLYING A SENSITIZING COATING '10 PAPER.

. Application iiled August 1, 1925. Serial No. 47,524.

My invention relates to improvements in means for applying coatmg to paper, or other fabric.

In the coating or sensitizing of paper or other fabric for photographic purposes, particularly blue-print and white-print papers, the solution is usually applied by drawing the material to be coated over a roller having the sensitized solution on its surface. Regardless of the particular method of (118- tributing the solution over said material,

however, it is always necessary to scrape the surplus solution from saidsurface. This is usually done by means of a glass scraper 1n the case of blue-print or white-print paper against which the paper is drawn. Various difliculties have been encountered, such as scufling of the paper surface and abrasions, which cause streaks in papers like blueprmts and white-prints; also the sizing material 1n the paper is, to a certain extent, removed 'from the aper. Such streaks and irregularities o n appear to be of minor 1mportance initially, but appear in greatly exaggerated form after the print has been developed.. These d1fiCl11tl6S, '1n the case of white-print paper, or blue line pr nt paper, are so serious as to greatly curtail the use of this paper and to render the manufacture of it unprofitable.

The 0 ject of this invention is to overcome these diificulties by providing means for removing the surplus solution from the paper or other fabric without adversely affecting the finishe'd product, and thus to render practical the use of white-punt paper in particular, and, in general, to establ 1s h a uniform grade of excellence for sensitlzed fabric of this character.

This improvement is effected b blowing the surplus solution from the fa me by a thin'sheet of air. In the form of the invention illustrated in the accompanying drawings, the air issues in a thin sheet from a horizontal slot in a tube and is directed substantially at right angles against the upwardly moving sheet of paper, a suitable backing being arranged behind said paper to maintain a fixed distance between the aper and theslot by preventing sald paper tom-being blown away from and $10 Fig. 1 in a side elevation oi-the apparatus.

2 is an end elevation thereof. 51g. 3 1s a section on line 3-3, Fig. 5, an

- 4 is a section on line 4-4, Fig. 5.

Fig. 5 1s a front elevation of the air ipe. The rear end of the ap aratus inclu esa frame having end standar s 10, which frame supports a jar 11 containing the sensitizing coating solution, a dry-box or heating chamber 12 being located at the upper part of said frame. Near the lower end of the standards is a pair of brackets 13 which 511 port a roll of paper 14 of the desired gra e or whatever material it is desired to coat.

The web of paper 15 passes upwardly as the roll is unwound, over a roller 16, which is preferably a brass roll, then around roll 17 which has a surface preferably of hard rubber, said roll rotating in a direction the reverse of the movement of the paper, as indicated by the arrows. From this .roll the paper passes upwardly past roller 18 into the drying chamber 12. The coating solution of fluid is fed to the coating roll 17 through a suitable hose 19 connecting with a pipe 20 having openings therein through which the solution descends onto the roller, a certain quantity of it being retained between the roller and the web of paper as the latter is leaving said roll. The surplus drains into the lower part of the enclosure 21 and flows througlai.

'fter issuing from a narrow slot in the upper end of the enclosure 21 slides over a fixed support 24. consisting referably of a sheet of copper against whic the paper is pressed by the sheet of air blowing against it at this point. ,e

The air issue; from a longitudinal opening in a tube 25 which is preferably tapered, having its larger ,endconnected to a blower .or other suitablesqurce of supply, and havslot is regulated by means of a clamping so that a substantial y uniform volume of air may issue from the slot at substantially an points thereof. Since the supply roll 14 may be of various different lengths, it is preferable to control the length of the slot. in accordance with the width of, the paper, and for this purpose, I provide shields 30,- preferably in the form of elongated sheet metal clips, which may he slipped over the lips26 near opposite ends of the slot, thereby obstructing the issuance of air and limiting the length of the slot to the distance between the inner ends of said clips. By sliding said clips back and forth the effective length of the slot may thus be varied.

With the arrangement described, the compressed air issues from the slot in a thin sheet which effectively removes thesurplus coating, after which the paper, in its further ascent, is dried in the heating chamber, the latter being heated by any suitable source, such as a gas heater 31. The enclosure 21 is-made preferably of-copper, and

serves also asan air shield completely enclosing the paper, as it is-being coated, from the time it enters the enclosure through a small'slot at the rear thereof until it reaches the small slot at the top thereof, thus keeping the air from coming in contact with the solution and evaporating the water from it. p v

The. use 0'frtll6 apparatus described, completely eliminates the trouble previously encountered, the resulting coated paper heingfree from scufling or abrasions, which result in streaks inthe finished print. The deposited solution is kept on the surface of the paper and is not rubbed unevenly into it, said solution is evenly deposited over the entiresurfaceas the air stream equalizes-the solution, and, furthermore, the deposit is perfectly clean and free from floating particles of sediment, etc, as the air stream floats the& particles down, whereasr the scraper would rub them into the surface. In addition, the amount of solution lettorr the surface of the paper may be controlaled to a meet by means of 'the' adjustable air slot and the. regulation of the pressure at the slot, or else at. the source by a by-pass- 32.

Instead of feeding the solution from the jar 11 to the. pipe 20, it may be circulated by means'oi a small pump from the jar '23 to said ii-grand the jar I1 omitted. Various other e nges may be made in the apparatus without departing from the spirit of the invention. Whereas the sensitizing solution applied by coating machines is usually ap plied to paper, it. has alsoibeeni the practice tofspplly: it to cloth-'andother fabrics, and

ing saidpaper to travel past said solution applyingv -mean s, means for blowing air against said solution coated paper, said means oomprisi an air discharge member ada ted to distri ute air across the width of sai paper with substantially uniform pres sure, and a backing for said paper, for supporting the entire rear surface thereof adjacent the region where said air strikes it. I

2; Apparatus for coating paper and the like, comprising rotatable means for applymg .a solution to the paper, means for causing said paper to travel past said solution applying means, means for blowing air against said solution coated paperto remove the surplus solution therefrom,-end-a backing for said paper supportingthe entire rear surface thereof adjacent the region Where said air strikes it. I

3, A device of the class described com rising a frame having a support'for a IQ of paper and the like thereon a coating roller also supported thereon, a source of sensitizing solution, a pipe connected with said source havin openings. therein fopdischargmg said so ution upon said roller,-means' for drawing saidv paper from said supply roll past saidcoating roller,- a conduit having an adjustable slotthenein arranged to direct a thin sheet of air'against said paper {after the sensitizing solution is [a bed thereto, and a; fixed support behind sai paper-vast which the latter slides as the air is being directed against the same, thereby holding said from said slot.

4. A machine for coating paper-and the like with a sensitizing solution comprising a solutionapplying means, pneumatic means for removing the surplus solution from the paper comprising a conduit with a tapered. extension and .a slot therein, means for varying the length of said slot, and means for varying the width of said slot.

5.;A device of the classdescribed com- :prisin-ga frame havinga support. for a roll of paper and.-the like thereon, a' coating roller also su ported thereon, a source.- of sensitizing so ution, a pipe connected with said source having-openings therein fordispaper at a, definite distance 10 paper and the like past the thin sheet of air against said pa er after the sensitlzing solution is apphe thereto,

and a fixed support behind said paper past which the latter slides as the air is being directed against. the same, thereby holding ssliid paper at a definite distance from said s 0t. 7

6. In a device of the class described, a coating roller, means for drawing a strip of same, means for enclosing said roller and paper during the coating, and means for blowing air against said paper above said enclosure to remove the surplus solution therefrom, said enclosure serving to prevent aeration of the solution on said paper adjacent said coating roller.

In testimony whereof, I have subscribed my name.

HAROLD J. BRUN K. 

